Heart transplant complications

Background

• Indications: end-stage heart failure refractory to standard medical/surgical treatment
• Transplanted heart is denervated
  • Resting rate between 90-100 bpm
  • Response to exertion/stress is blunted by lack of central mediated tachycardia, though can still respond to circulating catecholamines
  • Upregulation of catecholamine receptors
  • Atropine is ineffective (no Vagal nerve tone)

Immunosuppressant Medications

• Balance between immune suppression, rejection and susceptibility to infection
• Typical regimen includes: calcineurin inhibitor + antimetabolite + steroid
  • Calcineurin inhibitor
    • Cyclosporine
    • Tacrolimus
  • Steroids
    • Prednisone/Prednisolone
  • +/- Antimetabolite
    • Azathioprine
    • Mycophenolate mofetil (MMF)

Clinical Features

Rejection

• Patients monitored with surveillance biopsies regularly
• Spectrum of presentations, anywhere asymptomatic to in extremis
  • Features include dysrhythmias, decreased exercise tolerance, and infection may be clues

Infection

• Increased risk of opportunistic/severe infections
• Fever and other classic features may be absent due to immunosuppression

Signs/Symptoms of Congestive Heart Failure

• Due to various etiologies
• MI may present only with CHF symptoms

Medication Adverse Effects

• Prednisone
  • Hyperglycemia, psychiatric symptoms, poor wound healing, edema, hypertension
• Tacrolimus, cyclosporine
  • Neurotoxicity, tremor, hyperkalemia, nephrotoxicity, hypertension, hyperglycemia, gout
• Mycophenolate
  • Cytopenias, GI distress
• Azathioprine
  • Cytopenias, pancreatitis, hepatitis

Myocardial ischemia/CAD

• Pediatric recipients in particular at risk for graft CAD
• Due to denervation, transplant patients with ’’’NOT’’’ have pain with ACS

Evaluation

Workup dependent on presentation, considerations include:

• CBC, BMP, Mg/Phos
• Low threshold for infectious workup, including viral/fungal studies
• Tacrolimus, cyclosporine levels
• ECG
  • Patient’s native sinus node often preserved
    • → two P waves on ECG
    • donor P wave will be in 1:1 relationship with QRS, native P wave has independent rhythm
• CXR
  • May have relative "cardiomegaly" if donor was much larger than recipient
• CT Chest
  • May be required to diagnose PE, hypoxemia, pneumonia
• Echocardiography
  • Consider if signs/symptoms of heart failure

Management Considerations

• Consult/discuss with transplant team
• Rejection
  • Diagnosed by biopsy
  • Do not treat if stable, as steroids will muddy biopsy results
  • Methylprednisolone 1g IV if in extremis
• Dysrhythmias
  • Bradycardia will ‘’’NOT’’’ respond to atropine due to denervation
    • transplant patients with symptomatic bradycardia may respond to isoproterenol 1 μg/min, titrated slowly to max 4 μg/min
  • Transplant patients may be overly sensitive to adverse effects from adenosine
  • Sinus node dysfunction usually requires pacemaker placement
• See Immunocompromised antibiotics

See Also

• Transplant complications
• Neutropenic fever
• Immunocompromised antibiotics
• In-Training Exam Review